#include <Eigen/Dense>
#include <iostream>
using namespace std;
using namespace Eigen;
int main() {
  Matrix3d A;
  A << 1, 2, 1, 1, 2, 1, -1, 1, 2;
  A(0, 0) = 10;
  A(2, 2) = 20;
  //   A(3,3) = 30;
  cout << A << endl;
  auto b = A.transpose();
  cout << "after trans\n" << A << endl;
  cout << "trans\n" << b << endl;

  return 0;
}